1. Field of the Invention
The present invention generally relates to a music accompaniment playing (so-called "karaoke") system, and more particularly to a melody controlling apparatus for and a melody controlling method of performing a melody change in information to control a digital sound source such as a MIDI (Musical Instrument Digital Interface) apparatus. Here, the "melody" means the tonality (e.g. C major, A minor) of the music program, and the constructions of the rhythm and the chord (harmony) applied to the music program. The "melody change" means the change in the tonality which is owned by the original music program, or the change (arrangement) in the construction of the rhythm and the chord and so on.
2. Description of the Related Art
In a music accompaniment playing system, the composition of the music information which is the base of the accompaniment, is performed by use of a tonality (e.g. C major, A minor) suitable for the music field (genre) of the original music program. The arrangement thereof is performed by use of the rhythm and the chord etc. suitable for the music program at the time of composing the accompaniment music, so that the thus performed music is prepared as the accompaniment music information.
As a melody controlling apparatus for the music accompaniment playing system etc., there is an apparatus which has a plurality of accompaniment music information each corresponding to one of various music genres, and which selects and calls the accompaniment music information in accordance with the music genre requested by the user, and which performed the thus selected accompaniment music information, as disclosed in Japanese Patent Application Laid Open Hei No. 03-290,696.
As another type of melody controlling apparatus for changing the information of the original music program upon giving the actual performance, there is a key controller etc., which changes the key of the whole performance in accordance with the change in the key (sound key) of the sound voice of the user who is singing a song by the music accompaniment playing system.
However, the change in the accompaniment music information in the above mentioned performance controlling apparatuses, is limited in the range of the performance genre change which mainly consists of the change in the selection of the rhythm or the tempo. Otherwise, the change in the tonality is not performed by the above mentioned performance controlling apparatuses. Namely, such a bold arrangement of the music program over the whole music composition is not performed, by applying the change in the music construction including the characteristic sounds etc., which are composed of root sound of the music program as the base, according to the above mentioned performance controlling apparatuses.
Further, the feature of having a plurality of performance information with respect to a single music program, is contrary to the practical demand to input, into the limited amount of the memory device provided in the music accompaniment playing system, as many music programs as possible.
Furthermore, the key controlling function is provided to support singing, and to control the sound key of the whole music information to be performed. Thus, it is not the function for pleasure, to allow the listeners to listen to the music program as if it were the different music program by positively changing or arranging the music program.